It's looking like a bit of a Scrubs reunion once Cougar Town returns with new episodes around midseason. Zach Braff and Robert “The Todd” Maschio, and a few other stars from showrunner Bill Lawrence's other well known series, Scrubs, will be making some special appearances in a season 3 episode:
"TVline has learned exclusively that both former Sacred Heart residents have landed guest spots on a Season 3 episode of the ABC comedy, which returns at midseason. Details about each role are being kept under wraps for now, but we can tell you that Braff will appear in the flesh this time around, and not as the voice on another one of Laurie’s silly appetizer apps like he did in Season 2."
Joining Braff will be Sarah Chalke as a new love interest for Bobby, as well as Sam Lloyd returning as ukelele-strumming Ted and Ken Jenkins as Jules' dad.
Source: TV Line